Causes of jaundice with diagnosis and bio markers

All about jaundice, diagnosis,  jaundice sign and symptoms, with bio markers

Yellow discoloration of skin is seen in, Yellow pigment seen all over. This occurs by liver disease or hemolytic disorders. Urine also becomes dark-colored (yellow). due to Excess of bilirubin in the blood is the state of hy­perbilirubinemia.


jaundice

 

Definition Jaundice —

  • It is a yellowish discoloration of tissues due to depo­sition of biliruibin in tissues. Excess of bilirubin in the blood is the state of hy­perbilirubinemia. This occurs by liver disease or hemolytic disorders.
  • Jaundice can be seen most easily in eye in the sclera due to its high elastin content which is high sensitive to it, when the serum bilirubin is 3 or >3 mg/dl. Jaundice can also be present below the tongue. The skin also becomes yellowish  in light-skinned patients.
  • Later it appears greenish due to oxidation of bilirubin to biliverdin.
  • Yellow discoloration of skin is seen in —
  • · Jaundice
  • · Carotenoderma (due to eating carrots)
  • · Use of drug – quinacrine
  • · Exposure to phenols.
  • Carotenoderma —
  • No scleral discoloration seen like jaundice, so yellow discoloration of eyes not present. Pigment seen on pelvis, nasolabial folds,soles, forehead.

Jaundice —

  • Yellow pigment seen all over.
  • Urine also becomes dark-colored (yellow).
  • This indicates the presence of  direct increased bilirubin and therefore, presence of liver disease.
  • Bilirubin is a breakdown product of blood components , haeme. Bilirubin is formed in the  reticuloendothelial cells, mainly in the spleen and liver. Unconjugated bilirubin (insoluble bilirubin) is bound to albumin and transported to liver.
  • In the ER – (endoplasmic reticulum) bilirubin is solu­bilized by conjugation to glucuronic acid. The conju­gated bilirubin excreted into bile drains into the duode­num and passes to small bowel.
  • In the distal ileum and colon the conjugated bilirubin is again hydrolyzed to unconjugated bilirubin. The unconjugated bilirubin is reduced by gut bacteria to urobilinogens.
  • 90% of this urobilinogen is excreted in feces (orange colored).
  • 10% of this may enter the liver and 10% is excreted in urine.
  • The Van den Bergh method is used for estimation of direct (conjugated) bilirubin, indirect (unconjugated) bilirubin and total serum bilirubin.
  1. Normal serum bilirubin concentration is <1 mgj dl (0.2 to 0.9 mgjdl).
  2. Jaundice means serum bilirubin concentration >lmgjdl.
  3. Conjugated bilirubin is 0.3 mgjdl. Unconjugated bilirubin is 0.7 mgjdl.
  • Serum bilirubin falls very slowly even after the pa­tient is fully recovered because all the conjugated bi­lirubin may be bound to albumin and so its value in serum falls slowly because of the long half-life (2 weeks) of albumin.
  • Almost 100% of serum bilirubin is unconjugated. Unconjugated bilirubin is always bound to albumin and so not found in the urine.
  • A fraction of conjugated bilirubin only is excreted in the urine.
  • So, any bilirubin found in urine is conjugated biliru­bin.
  • Therefore, any bilirubin in urine means liver disease.

Blood~ RBCs breakdown occurs in ~Reticuloendot­helial cells of Liver and spleen ~Bilirubin (insoluble in water) ~Binds to albumin ~Bilirubin+Albumin ~ taken up by hepatocytes ~unconjugated bilirubin~ binds to ligandin in hepatocyte ~….. with help of

  • UDP …………. conjugated to glucuronic acid ~bilirubin
  • monoglucoronide and bilirubin diglucuronide.
  • (UDP – uridine diphosphate gucuronyl transferase.)

 

Approach to a case of Jaundice —

  • 1.Is the jaundice (elevation of serum biliru­bin) isolated (the only) finding?
  • 1. Unconjugated hyperbilirubinemia (or indirect hyperbilirubinemia) .
  • 2. Conjugated hyperbilirubinemia (or direct hy­perbilirubinemia)

2. Indirect hyperbilirubinemia

A. Hemolytic disorders

1. Inherited

  • Spherocytosis, Elliptocytosis
  • Sickle cell anaemia

 

2. Acquired

  • Microangiopathic
  • Paroxysmal nocturnal hemo­globinuria
  • Immune hemolysis

B. Ineffective erythropoiesis

  • Thalassemia
  • Severe iron deficiencies

 

C. Drugs —

  • Rifampicin, Probenecid

D. Inherited conditions

  • Crigler-Najjar types I and II
  • Gilbert’s syndrome

3. Direct hyperbilirubinemia Inherited:

  • Dubin Johnson syndrome
  • Rotor’s syndrome
  • There is elevation of serum bilirubin with other liver test abnormalities.
  • Hepatocellular conditions
  • Cholestatic conditions.

1. Hepatocellular conditions that may pro­duce jaundice

  • · Viral hepatitis A, B, C, D, E
  • · Herpes simplex
  • · Epstein Barr virus
  • · Alcoholic hepatitis
  • · Acetaminophen toxicity (dose-dependent)
  • · Isoniazid (Idiosyncratic)
  • · Vinyl chloride (toxin)
  • · Amanita (toxin of mushroom)
  • · Wilson’s disease
  • · Autoimmune hepatitis.

2. Cholestatic conditions that may cause Jaundice

That’s the brief description about jaundice, in future i will add about treatment and management about jaundice.